Capacitive sensor matrix

Does someone have ever made a capacitive matrix with Arduino ? I would-like to experiment an 8/8 matrix based on projective-capacitive principle :


The problem with this is that they interfere with each other. There is a commercial chip that does about 32 contacts but it gets a bit hairy up to that and beyond.

I've got some freescale e-field sensor ICs (MC33941) which I want to try out with arduino.. the chip allows for 7 individual electrodes and comes in a 24-pin SOIC chip

I wasn't sure how I could go about building the electrodes without fabricating some PCBs, but this guide might help - so thanks for that.

Are you thinking about using a particular chip for sensing?

There are/were some stick-on copper foil shapes (from Datak??? I think it was a maker of rub-on letters for front panels) that could be used to hand-tape PCB-equivalent boards. Some of those could be put on perfboard to make capacitive switches.


There are/were some stick-on copper foil shapes

If you can't get them then look at craft suppliers for self adhesive copper tape you can get it up to 3" wide. It is used for stained glass work, but I have used it to make ground planes on single sided perf board.

Below a 4*3 matrix project with Atmega8 I found 6mm conductive tape and will tray with two different patterns.